Light-Driven Catalytic Upgrading of Butanol in a Biohybrid Photoelectrochemical System
Year: 2017
Type: article
Abstract: This paper reports the design and preparation of a biohybrid photoelectrochemical cell (PEC) that can drive the tandem enzymatic oxidation and aldol condensation of n -butanol (BuOH) to C 8 2-ethylhexenal (2-EH). In this work, BuOH was first oxidized to n -butyraldehyde (BA) by the alcohol oxidase enzyme (AOx), concurrently generating hydrogen peroxide (H 2 O 2 ). To preserve enzyme activity and increase kinetics nearly 2-fold, the H 2 O 2 was removed by oxidation at a bismuth vanadate (BiVO 4 ) photoanode. Organocatalyzed aldol condensation of C 4 BA to C 8 2-EH improved the overall BuOH conversion to 6.2 ± 0.1% in a biased PEC after 16 h. A purely light-driven, unbiased PEC showed 3.1 ± 0.1% BuOH conversion, or ∼50% of that obtained from the biased system. Replacing AOx with the enzyme alcohol dehydrogenase (ADH), which requires the diffusional nicotinamide adenine dinucleotide cofactor (NAD + /NADH), resulted in only 0.2% BuOH conversion due to NAD + dimerization at the photoanode. Lastly, the application of more positive biases with the biohybrid AOx PEC led to measurable production of H 2 at the cathode, but at the cost of lower BA and 2-EH yields due to both product overoxidation and decreased enzyme activity.
Authors: Alexander W. Harris, Omer Yehezkeli, Glenn R. Hafenstine, Andrew P. Goodwin, Jennifer N. Cha
Institutions: University of Colorado Boulder, University of Colorado System
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2736716373